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Of these genera only the first is represented on the Pacific coast, and there, besides the normal form, is found a group of species (Dichirus Mann.), having the body clothed with long hairs, and the intervals between the striæ of the elytra marked with two rows of punctures; in them, too, the middle tarsi of the male are scarcely dilated.

Group III.-Harpall.

The anterior and middle tarsi usually strongly, sometimes only slightly dilated, clothed beneath with two rows of squamiform papillæ. The head is usually slightly narrowed behind the eyes. I have found it necessary to reduce the number of genera indicated in my synoptical table of this group, an undue prominence being there given to the form of the ligula and paraglossæ.

*

Mentum not toothed; anterior tarsi with the first joint elongated and dilated in the female;

Elytra with three rows of punctures.
Elytra with a single dorsal puncture.

Anterior tarsi of the female not dilated;

Mentum strongly toothed.

Mentum tooth very small, or none;

Last joint of maxillary palpi slightly elongated;

Thorax subquadrate.

Thorax rounded.

GYNANDROPUS. GYNANDROTARSUS.†

BRADYCELLUS.

HARPALUS. STENOLOPHUS.

Last joint of maxillary palpi nearly twice as long as the preceding (thorax flat, subcordate, with prominent hind angles). PHILODES. Harpalus includes Selenophorus Dej., which consists of the species having three rows of punctures on the elytra. Hairy and punctured Harpali (forming the division Ophonus) are not represented in North America. There is no special difference between Harpalus and Stenolophus, except the smaller size and rounded thorax of the species of the latter; in most of the species of Stenolophus the fourth joint of the dilated tarsi of the male is deeply bilobed, and the palpi are acuminate; but among the species of Harpalus proper there is much variation in this respect, as well as in the length of the first joint of the hind tarsi.

Philodes contains two species, Stenolophus alternans Lec. (Badister testaceus and Aepus testaceus Lec.), having three rows of

* Trans. Am. Phil. Soc., x. 384.

† It is quite possible that this genus will be found to belong to the preceding group.

punctures on the elytra, and the Californian S. tener Lec., without rows of punctures. The form is more elongated than that of any true Harpalus or Stenolophus, and the last joint of the maxillary palpi, besides being longer, is more conical, almost forming with the preceding a fusiform mass, as in Trechus. They are found in wet places, and are quite rare.

Tribe XIV.-POGONINI.

The ligula is free at the apex, with distinct paraglossæ; the palpi are slender, and the last joint is nearly cylindrical; the mentum tooth is distinct, emarginate at tip. The anterior tibiæ are slightly thickened, with a few apical spines; the two basal joints of the anterior tarsi are dilated in the male, with two rows of papillæ beneath. The antennæ have but two basal joints glabrous, the third is elongated and pubescent. The head has deep frontal impressions, and is slightly constricted behind. The epimera of the mesothorax are short, and but very slightly widened externally.

This tribe is represented in our fauna by the genus Patrobus alone; one species, P. longicornis Say, is found commonly under stones in the Atlantic region, the others are northern, and species are found on both sides of the continent.

The position of these insects is disputed by different authors. Schaum, the latest authority, ranges them with Pterostichini; but the difference in the number of dilated tarsal joints in the male seems to warrant their separation, and indeed almost their union with the next tribe, with which they were associated by Erichson. The pubescence of the antennæ nearly covers the third joint, a character found exceptionally (according to Schaum) in the tribe Pterostichini, but which is not seen in any of the species in our fauna.

The species of Patrobus having convex thorax have the eighth stria of the elytra confluent with the margin anteriorly; in those with flat thorax the stria is separate from the margin for its whole length.

Tribe XV.-TRECHINI.

In this tribe the ligula has eight bristles, and is free at the apex, with distinct and long paraglossæ; the palpi have the last

* Pogonus minutus Dej. is not found in the United States, as stated by him.

joint acuminate, not shorter than the penultimate joint. The mentum is toothed; the third joint, and even the second joint, of the antennæ is pubescent. The head has the frontal impressions long and deep, curved behind the eyes, forming a slight posterior constriction. The anterior tibiæ are either linear (Anophthalmus) or slightly dilated, not spinous at the tip. The anterior tarsi of the male have two somewhat obliquely dilated joints, furnished beneath with squamiform papillæ. The epimera of the mesothorax are short, and somewhat triangular. The elytra are rounded at the apex, with the eighth stria anteriorly confluent with the margin, and most frequently interrupted at the middle.

Two genera are represented in our fauna; both have the first stria of the elytra recurved at the apex.

Eyes wanting; anterior tibiæ linear.
Eyes large; anterior tibiæ slightly thickened.

ANOPHTHALMUS.
TRECHUS.

Anophthalmus Tellkampfii is found in the Mammoth Cave, Kentucky; other species will be found in our other caves, when scientific zeal shall cause them to be properly explored. Trechus is found on both sides of the continent, but only in northern regions. The European T. rubens has recently been found by Mr. H. Ulke in Nova Scotia. Trechus includes Epaphius.

I formerly placed Tachys in this tribe; by the definitions here given it belongs more properly to the next; but with the European genus Perileptus Schaum there is a very close osculation between the two tribes.

Tribe XVI.-BEMBIDIINI.

The ligula has but two bristles at the apex, which is free for a very short distance; the paraglossa are distinct, scarcely longer than the ligula; the penultimate joint of the palpi is obconical, and the last joint much narrower and shorter, so as to be subulate. The mentum is strongly toothed, and the tooth is usually emarginate. The two basal joints of the antennæ are glabrous, the third is pubescent. The form of the head and frontal impressions are variable. The anterior tibiæ are slightly spinous at tip, either squarely truncate as usual, or slightly dilated and obliquely truncate, with the outer angle a little prominent. The anterior tarsi of the male are usually somewhat obliquely dilated in the first and second joints, the first being much larger than the second, but in

Anillus, Pericompsus, and certain Tachys the tarsi of the male are not at all dilated. The epimera of the mesothorax are more or less triangular. The elytra are entire, and rounded at tip, with the eighth stria usually confluent anteriorly, or nearly so, with the margin sometimes widely interrupted, but usually entire.

Like the other genera of Carabidae containing very numerous species, Bembidium consists of groups of species differing greatly in form, and even in the structure of the parts of the mouth; but the characters being evanescent, cannot be used for the definition of genera.

Our genera are as follows:

Eyes wanting.

Eyes small, flat.

Eyes large or moderate, convex;

ANILLUS. LYMNÆUM.

Anterior tibiæ not dilated at the apex; elytra with scutellar stria; sutural stria not recurved at the apex. BEMBIDIUM. Anterior tibiæ slightly dilated and obliquely truncate at the apex; elytra · without scutellar stria; sutural striæ recurved at the apex; Elytra with the eighth stria interrupted or less deep at the middle.

Elytra with eighth stria very deep.

TACHYS. PERICOMPSUS.

Of Anillus and Lymnæum but single Californian species have yet been found; the other genera are widely diffused. Blemus anescens Lec. must be placed in Tachys, the smaller proportional size of the third joint of the antennæ not being sufficient for generic separation.

FAM. III.-AMPHIZOIDAE.

Mentum deeply emarginate, with a medial tooth; lobes obtusely rounded; ligula large, quadrate, corneous; gular

suture none.

Maxilla with the outer lobe narrow, glabrous, palpiform, but not biarticulate; the inner lobe curved, acute at the apex, sparsely ciliate, with spines internally.

Antennæ inserted under the front, behind the base of the mandibles; entirely glabrous, polished.

Prothorax with the epimera and episterna moderately distinct; prosternum produced behind over the mesosternum. Metasternum truncate behind, not reaching the abdomen.

Abdomen with six ventral segments, the anterior three

connate.

Legs slender, formed for running; anterior and middle coxæ small; globular cavities of the former not closed; posterior dilated internally, contiguous at the inner margin, extending also to the margin of the body, separating the side pieces of the metasternum from the first ventral segment.

Notwithstanding the searching analysis of the characters of Amphizoa insolens, made by Dr. Schaum in his Insecten Deutschlands, I must differ with my eminent friend regarding the interpretation of the characters, and still regard it as representing a distinct family, and not as a very aberrant Carabide. It is true that the characters it shows, with the exception of the metasternum truncate behind, individually are found in various anomalous Carabidæ, but the concentration of all of them in one object, with the addition of yet another, entirely unknown otherwise in the series of land carnivorous beetles, surely constitutes sufficient reason for regarding this single species as the representative of a distinct type, equal in value to the families which precede or those which follow.

In addition to the characters given above, I would mention: the head is broad, obtuse; the eyes very small; the labrum very transverse, sinuate in front; the palpi short, cylindrical; the side suture of the under surface of the prothorax is distinct, the others are nearly obliterated; the prosternum is broadly produced behind the coxa, and obtusely rounded at tip; the coxæ are not entirely enclosed, but are protected behind by the mesosternum. The latter is deeply concave behind, perpendicular in front, and is almost covered by the prosternum when the thorax is deflexed. The side pieces are diagonally divided, and the epimera reach the coxæ, which are small and round. The metasternum is prolonged and obtusely rounded between the middle coxæ, transversely truncate behind; the side pieces are triangular, without visible epimera; the posterior coxæ are large, flat, rounded behind, extending to the margin of the body, internally contiguous for a space nearly equal to the length of the metasternum, with a quadrate internal dilatation for the insertion of the legs, as in Carabidæ.

The legs are slender, rough with granulated points; the anterior tibiæ are not in the least degree sulcate internally, and have two small terminal spurs; the tarsi are glabrous, the joints rounded beneath; the claws simple. The elytra are twice as broad as the

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